The invention is based on a packaging machine as defined hereinafter. When containers such as bottles, vials and ampules are filled and sealed, they are delivered individually or in groups, in container receptacles, to a conveying device of the machining stations of a packaging machine. If different types and formats of containers are to be manipulatable in the packaging machine, then the container receptacles adapted to the particular containers have to be exchanged for one another. It is known, for instance, to store the container receptacles in magazines in format changing stations disposed at the ends of a packaging machine. The format changing stations have receptacles for the container receptacles, which are secured to a chain conveyor. The leading and trailing sides of the chain conveyor are arranged such that two receptacles are simultaneously located in the conveying plane of the packaging machine. Thus by means of a further conveyor device associated with the format changing station, a container receptacle can be removed from the conveyor device and at the same time exchanged for a different container receptacle from the format changing station. The format changing station of the known packaging machine is vulnerable to malfunction and expensive, however, because of the chain drive and the attendant effort and expense for driving and controlling it. Moreover, the holding capacity of the format changing station is limited by the number of receptacles, which makes for low flexibility of the packaging machine.